Picking up the robotic cubes that make up Modular Robotics' remote-control cars, sound-activated lights and other miscellaneous doodads brought on a sense of wonder and creativity I haven't felt for years. Each cube has a different function, and putting together a device of my imagination was as much a joy as it was a puzzle.

Pope Benedict XVI, the first pope to join Twitter, will post his last tweet on the social network at 11 a.m. ET, Thursday, right when he's expected to leave the Vatican by helicopter on his last day as pontiff. The papal Twitter account, @Pontifex, will be then be suspended until his successor is elected.